Incapable of sympathy or mercy; hardhearted; callous; cruel
The definition of dull is someone who is stupid or boring or something that is not shiny or something that is not sharp.
(Geometry) Of a triangle: with one obtuse angle.
Of, relating to, or characteristic of a pachyderm.
Indifferent or inattentive:
Being neither too much nor too little; moderate:
Difficult to alleviate or cure.
Find another word for thick-skinned. In this page you can discover 18 synonyms, antonyms, idiomatic expressions, and related words for thick-skinned, like: unfeeling, thick-skin, callous, dull, hardened, obtuse, pachydermatous, tough, unimpressible, insensitive and unconcerned.